MCQ
If work $W$ is done in blowing a bubble of radius $R$ from a soap solution, then the work done in blowing a bubble of radius $2 R$ from the same solution is
- A$\mathrm{W} / 2$
- B$2 \mathrm{~W}$
- ✓$4 \mathrm{~W}$
- D$2 \frac{1}{3} \mathrm{~W}$
✓
Answer
Correct option: C.
$4 \mathrm{~W}$
$W=8 \pi R^2 T \therefore W \propto R^2(T$ is constant $)$
If radius becomes double then work done will become four times.
If radius becomes double then work done will become four times.
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